Advent marks the time that Christians prepare for Christmas - getting ready for the big celebration of Jesus’s birthday. There are 4 Sundays in Advent but Advent calendars normally have only 24 windows.
Try this website for research:
http://resources.woodlands-junior.kent.sch.uk/customs/advent.html
or search Advent calendar ideas on Google for ideas….
Design an advent calendar or advent wreath to mark the days leading up to Christmas.